Moving items between two listboxes

Hi,
How do do this?
I want to be able to move one or more selected items between two listboxes, Listbox1, Listbox2 in my webpage. (Master page is used). Each listbox has a button to move the selected items form one listbox to the other. The items moved to another listbox should not show up in the listbox from which they were moved. (If there are,  say,5 items in Listbox1 and 3 are moved to Listbox2, these 3 should not show up in Listbox1). Lisbox1 is initially populated from the database.


Thanks for any help.



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